What to look in a truly dishwasher friendly non-stick cookware?

Look for one with a ten-year guarantee that states specifically is is dishwasher-friendly.

Keep the receipt.

There is a general rule that the more you pay, the longer it will last, but even just cooking in it if you can get more than a couple of years' useful life out of a frying pan without it getting sticky, you're doing well. Maybe 5 on the expensive stuff.

Personally, I wouldn't dream of putting my non-stick pans in the dishwasher. You can just about rinse them in hot water if they're good.

Would choosing steel over aluminum help longevity of the cookware considering daily dishwasher wash?

Not in my experience.

I use my dishwasher for essentially all my washing up but I am careful to load it so that things can't rub against the inside of the pans.

I've got a set of 3 non-stick aluminium saucepans bought several (at least 5) years ago which are as good as new. They go through the dishwasher every few days, and are stored stacked inside each other. I got them at sale price, and they were the best of a stores own brand (I thought they were discontinued but some sizes are still available). A lot of their use is frying or sweating, then adding wet ingredients to build a dish; for pure boiling tasks I tend to use my stainless pans where possible to save the non-stick for when it's needed.

My frying pans are one sandwich-base steel (probably ikea), one large aluminium (ikea), and one small aluminium (supermarket own brand), all at least 10 years old. The two smaller ones are now getting a bit sticky in places but still pretty decent; the larger is used less.

So moderately-priced steel and aluminium non-stick has been about the same for me.

My parents wash all their pans in the dishwasher. They haven't seen as much use as yours, but I am still surprised at how well they hold up. I cannot see much problems in their coatings. Sure, they are somewhat burnt and so less non-stick, but that's because of improper use of heat, not because of the dishwasher.

From what I have seen in their pans, and from your pictures, I would suggest that you can do the following:

• Choose ceramic-coated pans, rather than PTFE-coated ones.
• Look for pans with a very even finish, especially if they are PTFE. You can see in the photo that the hills-and-valleys surface on your current pans is working against you.
• I would probably recommend aluminum over steel, even though it doesn't seem to make a difference for Chris H and for my parents. It is obvious that your damage includes a lot of peeling, and the aluminum at the edges of the peeled areas is corroded by the detergent, which worsens the peeling. With bare (non SS) steel, the corrosion in these places will be rust, which is crumblier than corroded aluminum.
• A lot of your peeling has started on the rim of the pans. Try getting pans which are only nonstick-coated on the inside, and have enamel or something else on the outside. Bare stainless steel is good - it should also be better than aluminum wrt last point. You will have less damagable surface that way, and the rim is also highly endangered because of rubbing with lids.
• Since there was a version mentioning a brand: if a brand states that their pan is dishwasher-friendly, it is a good sign. Sure, it may be a lie (a lot of the claims surrounding nonstick pans are a lie, or at least exaggerated), but it improves your chances of getting more use out of the pan.
• Not shopping advice, but make sure you handle your pans with utmost care. Sometimes people do get away with using metal on theirs, or overheating them, but as you see in your case, the combination of scratches or heat-degraded coating and dishwasher detergent really damages the pan. You should gently use soft (wood or plastic) utensils on them, use them only for low-temperature cooking, and protect them while stacking (if you don't want to buy felt protectors, a piece of kitchen paper works). In the meantime, you mentioned that you don't use metal. Nevertheless, it is clearly visible that some of the coating was abraded in the newer pan, and it happened by rubbing against a flat surface (or against a wide edge, such as a spatula edge) and not by scouring dust in the detergent. If you are doing any rubbing with anything harder than wood, stop it.
• Again a part of maintenance: never expose your pans to thermal shock. Heat them slowly, with food already in them, and once hot, don't add cold (or room temperature) liquids to them.
• And lastly, get used to the idea that nonstick pans are an item with a limited timespan. If you use a nonstick pan everyday, you need both luck and perfect care for it to last maybe 3-5 years. With a dishwasher, its lifetime will certainly be shorter.